Hot Flashes and Your Heart: What's the Connection?

As to the women who really can't get off of hormones, I would urge them to make sure they are taking good care of themselves and are addressing these other risk factors. Lose some weight, get more exercise, monitor your blood pressure and cholesterol and glucose, and get treatment if it's recommended.

People also need to understand that we were never intended to be exposed to reproductive hormones for our whole lives. Estrogen is a general growth factor—it stimulates all types of tissue, including malignant tissue, so this is not all good. There is still this lingering feeling that estrogen reverses the aging process, that it's the elixir of life, and that if you start taking hormones at the right age, you can preserve yourself into old age. But for many diseases, age is the most important risk factor. Even if you're taking hormones, your arteries are getting older as you age. While estrogen is good for the arteries at some stages, at some point, it becomes a bad thing, and no one knows when that happens. But we do know that starting estrogen at older ages is not beneficial to the heart, and we suspect that continuing it for decades is not good either. There are much safer ways to prevent heart disease than taking hormones.  There are safer ways to reduce your cholesterol, for example. You can use statins at any stage, and they're going to be more beneficial, and have less risk overall, than hormones.

If a younger woman starts hormone therapy immediately after menopause, might she preserve healthier arteries for a longer time?
Using hormone therapy might keep your arteries slightly younger, that may well be true. But it would only be for a few years, when the risk of heart attacks is low anyway. It is unlikely in the long term to prevent the risk of cardiovascular disease. These results should not be taken to imply that if someone starts early, and continues to take it until they are much older, that any benefit will persist.  And remember, hormone therapy can come at the cost of increased risk of breast cancer, stroke and blood clots.

Do you think this correlation between increased risk of heart risk factors found in postmenopausal women having hot flashes, also applies to younger women who have hot flashes prior to menopause?
It is a possibility; I am sure this will be investigated now.

Do these results apply to women who take bioidentical hormones?
This study used " synthetic" hormones, and some people think that natural hormones are better. But from a physiological point of view, a substance either works or it doesn't, and the original form of the hormone is quite irrelevant. Whether using estradiol [the form of estrogen used in bioidentical hormones] makes a difference, who knows. But if I had to hazard a guess, I would say that any estrogen taken orally has much the same effect as we found.  The route of administration makes a difference. Transdermal patches do not increase the likelihood of blood clots. In that way, they appear to have an advantage. But there has not been an adequate number of trials on transdermals to know whether it reduces the risk of heart disease and stroke and breast cancer.

What future studies do you expect will be done with the WHI data?
We want to do more refinements and find out whether there's a difference in risk factors between women who start using hormone therapy immediately after they reach menopause, and those who wait four or five years to start it.  We will look at that in a future paper. This is especially important in terms of breast-cancer risk. There are other studies that indicate that if you change your level of hormones—either up or down—your risk of breast cancer goes down for a while, but then comes back up. For example, one approved treatment for breast cancer is to give someone a high dose of Premarin [an oral synthetic form of estrogen]. For some reason, if you have breast cancer and you bump up your estrogen, it retards tumor growth for a while.  If you block the estrogen, the risk also goes down. But both effects stop after a while. We want to know more about that.

© 2007